Many canister-type vacuum cleaners have traditionally been operable in either the horizontal orientation or the vertical orientation.
For instance, U.S. Pat. No. 3,755,992 to Ylien discloses a vacuum design for collecting lawn-related debris which does not use a filter element. Instead, a screen is placed across the opening between the fan and the canister to prevent large particles from entering the canister. In this construction, the device can only be utilized in the horizontal position.
U.S. Pat. No. 4,193,161 to Scott discloses a vacuum apparatus which may be moved between a use position and a dumping position. In this construction, it is only possible to utilize the apparatus with an upright canister vacuum.
U.S. Pat. No. 2,018,207 to Giambertoni discloses a vacuum cleaner designed to reduce noise of the motor during operation. The device includes a filter cowl within the casing defining a return flow passage for air flow from the suction pump, thereby deadening the sound of a motor. In this configuration, the device is incapable of being used in both the vertical and horizontal orientation.
U.S. Pat. No. 3,279,157 to Andersson-Sason et al discloses a suction cleaner having a removable dust bag including a second fine filter adjacent the outlet to remove fine dust particles which manage to get through the dust bag before the air is discharged into the room. The disclosed device in only operable in the horizontal position.
Traditionally, vacuum cleaners have positioned the motor in such a location as to prohibit the removal of the motor and filter in conjunction with the cover of the canister enabling the entire canister to function as a storage location for debris.
For example, U.S. Pat. No. 3,653,189 to Miyake et al discloses a horizontal canister vacuum wherein the filter element remains with the canister portion when the motor/fan assembly and cover are removed. In this construction, it is necessary to first remove the motor/fan assembly and the cover as well as the filter assembly prior to emptying the canister.
U.S. Pat. No. 2,962,118 to Lee et al discloses an electric vacuum cleaner having an entire motor/fan assembly within the canister in combination with a pair of air plenum chambers to achieve a quiet motor which is vibration-free during operation. The device relies upon a radial diffusion of discharged air in cooperation with a baffle to decrease the noise of the motor during operation. In this construction, because of the location of the inlet along the side wall of the canister, the entire space of the canister may not be used for collection of dust and debris.
Conventional vacuum cleaners have not packaged the motor/fan assembly in a clam-shell configuration to direct air flow to cool the assembly. For instance, U.S. Pat. No. 3,458,891 to Grellsson discloses a suction cleaner having an inlet at one end and a first outlet located in the middle of the canister at the bottom thereof. Air then flows through an air duct to a fine filter at the opposite end of the canister from the inlet improving the quality of air which is released at the second outlet from the canister. This device does not direct air flow through the motor to improve cooling.
U.S. Pat. No. 3,524,211 to Wolf discloses a vacuum cleaner with an air direction for directing an air stream against the interior wall of a dust bag to clear it from debris and dust, thereby maintaining sufficient suction. The device is not capable of operation in both the horizontal and vertical orientation. Nor is the direction means for directing the air stream used to improve cooling of the motor.
U.S. Pat. No. 4,797,072 to Berfield et al and related U.S. Patent No. 4,836,753 discloses a portable electric blower having a separate main air flow through the blower from another air flow past the motor which operates the blower. The device has an upper and lower housing and a motor cap such that there is a space therebetween defining a cool air pathway for cooling the motor. In this configuration, the motor is not cooled by the vacuuming air but clean air drawn in through the motor cap by a second fan.
The present invention incorporates many of the known benefits of canister vacuum cleaners while improving the ease of use, debris storage and removal and the method of cooling the motor/fan assembly.